ch-remote: switch to argh

Since argh does not support `--option=value`, we need to change the
integration test code to become `--option value`.

Signed-off-by: Wei Liu <liuwe@microsoft.com>

Cargo.toml

@@ -26,6 +26,7 @@ strip = true
 [dependencies]
 anyhow = "1.0.68"
 api_client = { path = "api_client" }
+argh = "0.1.9"
 clap = { version = "4.0.32", features = ["wrap_help","cargo","string"] }
 epoll = "4.3.1"
 event_monitor = { path = "event_monitor" }